Occupational Exposure at Mobile Communication Base Station Antenna Sites

摘要

For the assessment of safe distances which guarantee that the occupational exposure of persons working at mobile communication base station antenna sites complies with the relevant guidelines, numerical computations of the electromagnetic field and SAR distributions inside human body models with various body weights of 42, 70, and 110 kg in front of six widely-used single-, dual- and multi-band antennas are presented. The maximum whole-body averaged SAR always occurs for a centered position of the human body with respect to the main beam direction. For positions of a person beside and behind the antenna the absorption is drastically reduced. It turns out that for each antenna the whole-body SAR of the 42-kg body model is the limiting factor for the compliance distance. Compared to the 110-kg model the 42-kg model generates whole-body SAR values which are larger by a factor of approx. 1.7 on average for the considered antennas. Computed SAR values are related to the recommended basic restrictions (0.4 W/kg whole body SAR) and represented as maximum permissible radiated power levels as a function of antenna-to-body distance.